Beacon



C. WHITMAN May 26, 1936.

BEACON Filed Sept. 14, 1929 atto: nu*

Patented MayV 2d, 19.36.

UNITEDV STATES,

PATENT oFFicE BEACON Channing Whitman, Buffalo, N. Y., assignor to Flexlume Corporation, Tonawanda, N. Y., a corporation of New York 'll'his invention relates to improvements in beacons of the kind in which neon or other suitable electrpluminescent tubes are employed and proposes a construction which, altho available for other' purposes, is especially desirable as a warning marker to indicate to aviators the presence oi dangerous obstacles, such as towers carrying high voltage lines.

The use o f neon ytubes for this purpose is particularly desirable because of the fog penetrating power of the light produced by such tubes. Altho such a tube possesses this desirable characteristic, the length of itsvlife -is uncertain, and for I this reason its arrangement and connection in the ordinary manner would be objectionable for the particular purpose in view since its failure would permit the obstacle to remain unmarked until such failure was noted and remedied. Even -a failure for a short period,A a matter of hours, might result in an accident, particularly if the obstacle were near an airportor along a I in the event 'oi' failure of a tube another will automatically come into operation with characteristics which will indicate to one familiar with the installationthat it has succeeded in operation the tube with which the operation started. This fact can be noted by a simple inspection of the marker when illuminated and thus the defective tube can be replaced, the marker contlnV uing in operation until the replacement is made, assuming, as will be the fact in connection with a regular and orderly inspection, that the rey placement is made .within a reasonable time.

The invention contemplates the arrangement in any desired manner of a plurality of electroluminescent tubes of varying ,resistances and connected in parallel. Preferably the variations of resistance are obtained by using tubes of dif-l ferent' lengths. In such an arrangement the current, taking the path of least resistance, efi'ects thev illumination of the shortest tube in the group the other tube or tubes remaining inactive until the failure of the 'illuminated tube at which time the path of current is immediately A further object is to provide a marker in which shifted to include the next longer tube, the particular tube illuminated at any one time serving to indicate the condition of the remaining tube or tubes in the group.

An embodiment of the invention is illustrated t in the accompanying drawing in which: Y

Figure 1 is a plan view of an obstacle marker in which thefeatures of the invention are incorporated.

Figure 2 is an end view ofthe same. lu

Figure 3 is a longitudinal section through the body ofthe marker.

Figure 4 is a fragmentary section of the prei'erred type of electroluminescent tube with which the marker is equipped.4

The obstacle marker may be of any appropriate shape or form. As shown itis in the form of a 'l'. It may be provided with any suitable number of pairs or groups of tubes operating successively in the manner generally described.

The marker consists of a casing C in iwhich all operating parts except the tubes are mounted and which is of T shape, being preferably so arranged that its central leg and its end bar are in a horizontal plane. In the construction illustrated the marker is provided'with two pairs of tubes, the tubes of one pair A being arranged above the central leg of the casing and the tubes of the other pair Bbeing arranged in front of the end leg of the casing, the tubes of pair A extending horizontally and being in a common horizontal plane andthe tubes of pair B extending horizontally' y and being in a common vertical plane. The tubes of pair A are designated 5 and 6 respectively and the tubes of pair B are designated 1 and 8 re- 35 spectively. -In'pair A the tube 5 is the shorter tube and the tube 6 is the longer tube and in pair B the tube 'l is the shorter tube and the tube 8 is the longer tube. Each pair of tubes preferably has its own multiple circuit and at the start 4 oi.' the operation ofv the beacon the shorter tubes of, each pair are simultaneously illuminated. While the diiferences between thelengths of the vtubes of a pair together with the differences in tube of each pair is operating, the differentiation between the tubes of a pair may be made more vmarked, if desired. 1

Altho any desired type of tube may be' em-v ployed I preferably employ a tube of the construcminal portions of the tube, the casing having openings registering with said receptacles through which the terminal portions are inserted.

Suitable transformers I2 and I3 are mounted within the casing C, the primary or low voltage sides of the transformers being connected in parallel to a suitable source of energy (not shown) by the line wires Il and I5. The tubes 5 and 6 of pair A are connected in parallel as by wires I6 and I1 to the secondary or high voltage side of the transformer I2 while the' tubes 1 and 8 of pair B are similarly connected as by wires I8 and I9 to the high voltage side of the transformer Il.

Fromthe arrangement illustrated it will be noted that upon the connection of the line wires I 4 and I5 to a. suitable source of supply, the current will pass through wire I6, the shorter tube 5, and wire I'I back to the transformer I2, no current at all passing through the longer tube 6 which offers greater resistance to passage of the current than the tube 5. In like manner and at the same time the current will pass through wire I8, the shorter tube 1 and .wire I9 back to the transformer I3, no current at all passing through the longer tube 8 on account of the greater resistance which it offers. However, each of the shorter tubes 5 and 1, upon failure, will oil'er a greater resistance to the flow of 'current than the corresponding larger tubes 6 and 8 and the resistance in a shorter tube increasing suiliciently the current will change its path to include theV corresponding longer'tube. f It is to be noted that the voltageA required to` start an electroluminescent tube is much greater than that required to maintain it in an illuminated condition. For instance, where a tube is of such length as to require approximately 14,000 volts to start the ow of current, K10,000 volts would ordinarily be suillcient to maintain the operation. With this in mind, it will be understood that if for example, two tubes are connected in parallel, the longer tube requiring 14,000 volts to start it and the shorter tube requiring only 12,000 volts, then the shorter tube will be illuminated when the voltage of the current from the source of supply has been raised to 12,000 volts. Thereupon, as the resistance of the tube .falls to a normal operating value, the trans.-

former will immediately reduce the voltage to in the neighborhood of 9,000' volts, this E. M. F. being sufficient to maintain the operation. During the continued use of this shorter tube, and as the gaseous conducting medium therein is gradually dissipated, its resistance builds up to and approaches the resistance of the longer tube, that is eration and the transformer will immediately reduce the voltage to this amount.

From the example given it will be obvious that the two tubes will produce a light of substantially uniform intensity over a period of time equal to the sum of their lives and that the tubes will not become ineffective for any appreciable length of time during the period that the current shifts from the shorter tube to` the longer tube, this being due, as mentioned heretofore, to the fact that as soon as the F. required to illuminate the shorter tube has become suilicient to start the longer tube and does start such tube, the E. M. F. required to illuminate the longer tube is immediately reduced to such an extent as to be entirely inadequate to affect the shorter tube. For this reason it is impossible at the time that the resistance of the shorter tubes has been built up to the starting resistance of the longer tubes to have a condition where the path of the current will shift back and forth between the two tubes. In this connection it is to be understood that when the dissipation of the gaseous conducting medium in a tube reaches an advanced stage the operating voltage of the tube is not only increased but the brilliancy of the tube is materially impaired. The relative starting voltages of the tubes are, therefore, predetermined so that the illumination of a substitute tube will be effected before the gaseous conducting medium in the tube which it is to succeed has become dissipated to such an extent that the brilliancy of the latter is reduced to a point where it is unsuitable for the purpose in view. Likewise it is to be understood that if the tube which is initially illuminated shouldl fail for any other.reason, as

for example by being broken, the illumination of the substitute tube will be automatic and insfantaneous. An advantage obtained by this arrangement of tubes is that the particular tube illuminated serves to indicate the condition of the other tubes in its group, that is to say, in the form illustrated, when the longer tube 6 is illuminated it is a warning that the shorter tube 5 has failed and should be replaced, the longer tube substituting in the meantime for the inactive shorter tube until such replacement. l It will, of course, be obvious that the particular arrangement or number of tubes may be varied depending, in each instance, upon the purposes in view, the arrangement shown being merely for the purpose of illustration..

Having fully described my invention, vI claim:

1. A beacon or similar device including a support and a plurality of exposed gaseous discharge tubes which are connected in parallel and which are located in relatively close proximity with respect to one another, each of the said tubes being adapted to provide a light of substantially thesame intensity, the said tubes being illuminated one at a time as the breaking down of one tube automatically effects the illumination of a companionrtube of greater resistance, whereby to provide a continuous light of substantiallyV uniform intensity, the resistances of said tubes increasing `progressively in such degree that their order of illumination is certain and predetermined, the arrangement of said tubes upon said support being predetermined and in accordance with their order of illumination, whereby the tube which is illuminated at any particular' time serves to indicate whether there has been a failure of any of the remaining tubes and if there has been such a failure what particular tubes are involved.

2. A beacon or similar device including a support and avplurality of differently shaped exposed gaseous di'scharge tubes which are rconnected in parallel and which are located in relatively close proximity with respect to one another, each or the. 'said tubes being adapted to provide a light of substantially the same intensity, the said tubes being illuminated one at a time as the breaking down of one tube automatically effects the; illumination of a companion tube of greater resistance, whereby to provide a continnous -light o2 substantially uniform intensity,

the resistances of said tubes increasing progressively in such degree that their order of illumination is certain and predetermined, 'said tubes progressively increasing in length and'their arrangement upon said support being in accordance with their order of illumination, whereby the tube which is illuminated at any particular time serves to indicate whether there has been .a failure of any of the remaining tubes-and if 

